On Sat, Oct 08, 2005 at 09:02:36AM +0200, Stefan Lucke wrote: > On Freitag, 7. Oktober 2005 21:45, Ville Syrjälä wrote: > > On Fri, Oct 07, 2005 at 09:32:59PM +0200, Stefan Lucke wrote: > > > Hi, > > > > > > when using stretchblit for downscaling 16:9 to 4:3 interlaced TV, I > > > noticed some bad filtering effects. > > > > > > When I understood that right, downscale filters are described in > > > G440 external june15 page 3-217. Directfb's matrox gfx driver sets > > > this in matrox3d.c matroxTextureTriangles(), to MIN_ANISO. > > > > Actually I don't think ANISO does anything beyond BILIN without > > mipmapping. Also on G400/G450 aniso requires multitexturing to be enabled > > and is still prone to lockups. At least that was my experience when > > playing around with the Mesa mga driver. G200 doesn't support aniso at > > all. G550 seems to be the only one to support it properly. > > > > > Are other > > > values more suitable for doing that kind of filtering ? Or should > > > displaying downscaled interlaced video be done in another way ? > > > > > > Separte fields of a frame, > > > - downscale field 1, show field 1, > > > - downscale field 2, show field 2, > > > > Yes, fields should be scaled independently. I've though about doing that > > but never needed it enough :) > > Thanks for your reply but that's not the answer I wished to get. A easy > workaround for resolving that is getting a 16:9 TV ;-) , so no need to > downscale. > > So I think I know how to separate a frame into separate field buffers. > If a given frame has 576 lines I need 2 surfaces of 288 lines. Drawing > has to be done with stretchblit from YUV2 (field1) surface to an RGBA > surface, which has been allocated with DSCAPS_SEPARATED, upper half. > Same has to be done for field2 (RGBA lower half).
That should work. But it would be better to add proper support for independent field blitting to DirectFB. > Or is this possible with one stretchblit from YUY2 DSCAPS_SEPARATED > allocated surface to one RGBA suface with the same capability ? That should work too. > At least a simple test for setting the CRTC2 layer configuration with > DSCAPS_SEPARATED set, failed. That's because I didn't add support for it in the driver. The hardware does support it though. > Setting that flag to the source YUV2 > surface had no visible effect on the stretchblit operation. Currently DSCAPS_SEPARATED only affects DSBLIT_DEINTERLACE behaviour. -- Ville Syrjälä [EMAIL PROTECTED] http://www.sci.fi/~syrjala/ _______________________________________________ directfb-users mailing list [email protected] http://mail.directfb.org/cgi-bin/mailman/listinfo/directfb-users
